Study on the Tribological Mechanism of Ultrafine SiO2/MoS2 Powders in Complex Calcium Sulfonate Grease

2021 ◽  
Vol 69 ◽  
pp. 77-87
Author(s):  
Bo Rui Yang ◽  
Fang Xia Zhao ◽  
Peng Peng Wang ◽  
Zhen Zhong Zhang
Keyword(s):  
Friction Pair ◽  
High Hardness ◽  
Tribological Performance ◽  
Ball Bearings ◽  
Complex Calcium ◽  
Friction Mechanism ◽  
Calcium Sulfonate ◽  
Chemical Constitution ◽  
Research Objects ◽  
Repairing Effect

The purpose of this work was to study and further clarify the anti-wear and anti-friction mechanism of ultrafine SiO2/MoS2 powders in the complex calcium sulfonate grease. In this paper, 15nm nanoSiO2, 1μm MoS2 and commercial NLGI Grade No.2 complex calcium sulfonate grease were used as the research objects, SEM, EDS and XPS were used to study the morphology, composition and film chemical constitution of the long friction wear spots of grease containing single nanoSiO2 powder, ultrafine MoS2 powder and the two compound powders, which formed in the process of four ball long friction. The results show that nanoSiO the grease plays a role in filling the undercut, ball bearings and polishing and forming high hardness Ca3Fe2(SiO4)3 and part of Fe2O3 anti-wear films in the process of long friction. The ultrafine MoS2 powder has a self-repairing effect to fill the grooves,forming the MoS2, MoO3 anti-friction films and Fe2(SO4)3 anti-wear film. The two powders in the composite grease have a synergistic effect, acting on the friction pair together, and simultaneously forming self-repairing anti-friction and anti-wear films, thereby further improving the tribological performance of the base grease.

Synergistic Effects of MoDTC and Overbased Calcium Sulfonate Additive

2013 ◽  
Vol 651 ◽  
pp. 73-76 ◽  
Author(s):  
Zhao Zhou ◽  
Yan Qiu Xia ◽  
Xiang Yu Ge
Keyword(s):  
Sliding Friction ◽  
Synergistic Effects ◽  
Tribological Performance ◽  
Wear Properties ◽  
Sulfonate Additive ◽  
Alkyl Benzene ◽  
Friction Tester ◽  
Calcium Sulfonate ◽  
Alpha Olefin ◽  
Pure Poly

The synergetic effects of molybdenum dialkyldithiocarbamate (MoDTC) and overbased liner alkyl benzene synthetic calcium sulfonate (OBCaS) on the tribological performance of lubricant were investigated using reciprocating ball-on-disk sliding friction tester. The results showed that the two kinds of additives with a certain range of concent ration could improve tribological properties of alone MoDTC. The mass percent of 0.5% MoDTC and 2% OBCaS in pure poly-alpha-olefin (PAO) has the best friction reducing and anti-wear properties.

Study on the Hole-Wedge Effect of Friction Pair

2014 ◽  
Vol 494-495 ◽  
pp. 428-431
Author(s):  
Zhi Hong Han ◽  
Shu Yang Liu
Keyword(s):  
Friction Pair ◽  
Tribological Performance ◽  
The Self ◽  
Wedge Effect

The self-circulating compensation of lubrication was modeled ,a ferrofluid microcirculating trust bearing was designed,which showed that: the self-circulation compensation of colloidal lubrication can improve the tribological performance significantly.

Tribological Properties of the Overbased Calcium Sulfonate Complex Greases Containing Different Lubricant Additives

2013 ◽  
Vol 645 ◽  
pp. 133-136
Author(s):  
Peng Qiao ◽  
Yan Qiu Xia ◽  
Xiang Yu Ge
Keyword(s):  
Ionic Liquid ◽  
Tribological Properties ◽  
Friction And Wear ◽  
Sliding Friction ◽  
Tribological Performance ◽  
Mining Equipment ◽  
Wear Properties ◽  
Friction Tester ◽  
Calcium Sulfonate ◽  
Friction And Wear Properties

Overbased calcium sulfonate complex greases have excellent friction and wear properties and have been widely used in metallurgy and mining equipment. The effects and tribological performance of molybdenum dialkydithiocarbamate (MoDTC) and ionic liquid 1-(2-hydroxyethyl)-3-methylimidazolium bis (trifluoromethylsulfonyl) imide ([C2OHMim][NTf2]), 1-(2-hydroxyethyl)-3-hexylimidazolium bis (trifluoromethylsulfonyl) imide ([C2OHHim][NTf2s]), added in overbased calcium sulfonate complex grease as additives were investigated by using reciprocating ball-on-disk sliding friction tester. The results showed that the two kinds of additives with a certain range of concentration could improve the tribological properties of greases.

scholarly journals Localized Laser Dispersing of Titanium-Based Particles for Improving the Tribological Performance of Hot Stamping Tools

2020 ◽  
Vol 4 (3) ◽  
pp. 68
Author(s):  
Stephan Schirdewahn ◽  
Felix Spranger ◽  
Kai Hilgenberg ◽  
Marion Merklein
Keyword(s):  
Surface Engineering ◽  
Hot Stamping ◽  
Research Work ◽  
High Hardness ◽  
Tribological Performance ◽  
Future Research ◽  
Geometrical Shape ◽  
Engineering Technology ◽  
Friction Forces ◽  
Tool Surface

Within the scope of this work, a new surface engineering technology named laser implantation has been investigated, in order to improve the tribological performance of hot stamping tools. This technique is based on manufacturing highly wear-resistant, separated, and elevated microfeatures by embedding hard ceramic particles into the tool surface via pulsed laser radiation. Hence, the topography and material properties of the tool are modified, which influences the thermal and tribological interactions at the blank-die interface. To verify these assumptions and to clarify the cause–effect relations, different titanium-based particles (TiB2, TiC, TiN) were laser-implanted and subsequently analyzed regarding to their geometrical shape and mechanical properties. Afterwards, quenching tests as well as tribological experiments were carried out by using titanium-diboride as the most promising implantation material for reducing the tribological load due to high hardness value of the generated implants. Compared to conventional tooling systems, the modified tool surfaces revealed a significantly higher wear resistance as well as reduced friction forces while offering the possibility to adjust the thermal interactions at the blank-die interface. Based on these results, a tailored tool surface modification can be pursued in future research work, in order to enhance the effectiveness of the hot stamping technology.

scholarly journals Numerical investigation of the tribological performance of micro-dimple textured surfaces under hydrodynamic lubrication

2017 ◽  
Vol 8 ◽  
pp. 2324-2338 ◽  
Author(s):  
Kangmei Li ◽  
Dalei Jing ◽  
Jun Hu ◽  
Xiaohong Ding ◽  
Zhenqiang Yao
Keyword(s):  
Reynolds Number ◽  
Aspect Ratio ◽  
Stokes Equations ◽  
Hydrodynamic Lubrication ◽  
Friction Pair ◽  
Hydrodynamic Pressure ◽  
Tribological Performance ◽  
Textured Surfaces ◽  
Texture Density ◽  
Micro Dimple

Surface texturing is an important approach for controlling the tribological behavior of friction pairs used in mechanical and biological engineering. In this study, by utilizing the method of three-dimensional computational fluid dynamics (CFD) simulation, the lubrication model of a friction pair with micro-dimple array was established based on the Navier–Stokes equations. The typical pressure distribution of the lubricant film was analyzed. It was found that a positive hydrodynamic pressure is generated in the convergent part of the micro-dimple, while a negative hydrodynamic pressure is generated in the divergent part. With suitable parameters, the total integration of the pressure is positive, which can increase the load-carrying capacity of a friction pair. The effects of the micro-dimple parameters as well as fluid properties on tribological performance were investigated. It was concluded that under the condition of hydrodynamic lubrication, the main mechanism for the improvement in the tribological performance is the combined effects of wedging and recirculation. Within the range of parameters investigated in this study, the optimum texture density is 13%, while the optimum aspect ratio varies with the Reynolds number. For a given Reynolds number, there exists a combination of texture density and aspect ratio at which the optimum tribological performance could be obtained. Conclusions from this study could be helpful for the design of texture parameters in mechanical friction components and even in artificial joints.

scholarly journals Optimizing the tribological performance of DLC-coated NBR rubber: The role of hydrogen in films

Friction ◽  
2021 ◽  
Author(s):  
Changning Bai ◽  
Li Qiang ◽  
Bin Zhang ◽  
Kaixiong Gao ◽  
Junyan Zhang
Keyword(s):  
Surface Energy ◽  
High Hardness ◽  
Adhesive Force ◽  
Film Structure ◽  
Tribological Performance ◽  
Butadiene Rubber ◽  
Water Contact ◽  
Hydrogen Incorporation ◽  
Dlc Film ◽  
Impacted Load

AbstractDiamond-like carbon (DLC) films directly deposited on rubber substrate is undoubtedly one optimal option to improve the tribological properties due to its ultralow friction, high-hardness as well as good chemical compatibility with rubber. Investigating the relationship between film structure and tribological performance is vital for protecting rubber. In this study it was demonstrated that the etching effect induced by hydrogen incorporation played positive roles in reducing surface roughness of DLC films. In addition, the water contact angle (CA) of DLC-coated nitrile butadiene rubber (NBR) was sensitive to the surface energy and sp2 carbon clustering of DLC films. Most importantly, the optimum tribological performance was obtained at the 29 at% H-containing DLC film coated on NBR, which mainly depended on the following key factors: (1) the DLC film with appropriate roughness matched the counterpart surface; (2) the contact area and surface energy controlled interface adhesive force; (3) the microstructure of DLC films impacted load-bearing capacity; and (4) the generation of graphitic phase acted as a solid lubricant. This understanding may draw inspiration for the fabrication of DLC films on rubber to achieve low friction coefficient.

Tribological Properties of Complex Calcium Sulfonate Grease with Ultrafine SiO2/MoS2 Powders

2021 ◽  
Vol 66 ◽  
pp. 35-44
Author(s):  
Li Ming Wu ◽  
Bo Rui Yang ◽  
Fang Xia Zhao ◽  
Zhen Zhong Zhang
Keyword(s):  
Particle Size ◽  
Tribological Properties ◽  
Mass Ratio ◽  
Complex Calcium ◽  
Wear Scar Diameter ◽  
Load Range ◽  
Calcium Sulfonate ◽  
The Coefficient Of Friction ◽  
Addition Amount ◽  
Base Grease

For the development of complex calcium sulfonate grease containing ultrafine SiO2/MoS2 powders with self-reparing performance. On the basis of the dispersion of the nanoSiO2 particles, the effects of particle size,addition amount,load and the mass ratio of nanoSiO2 to ultrafine MoS2 powders on the tribological properties of commercial No.2 complex calcium sulfonate grease were systematically studied by four ball friction and wear tester. The results show that suitable particle size and addition amount of single SiO2 and MoS2 powders can significantly reduce the coefficient of friction (COF) and the wear scar diameter (WSD) of the grease. The composite of nanoSiO2 and MoS2 powder can broaden the load range of base grease and further improve the tribological properties of complex calcium sulfonate grease. When the mass ratio of nanoSiO2 powder to MoS2 powder is 3:7 and the total addition amount is 0.8wt%, the COF and the WSD of the grease are decreased by 53.64% and 27.08%, respectively, compared with the base grease. The two powders in the composite grease have synergy effect for improving the tribological performance and the friction stability of the grease during the process of long friction.

scholarly journals The Effect of Honing Angle and Roughness Height on the Tribological Performance of CuNiCr Iron Liner

Metals ◽  
2019 ◽  
Vol 9 (5) ◽  
pp. 487 ◽  
Author(s):  
Ma ◽  
Liu ◽  
Wang ◽  
Wang ◽  
Huang ◽  
...  
Keyword(s):  
Smooth Surface ◽  
Friction And Wear ◽  
Piston Ring ◽  
Friction Pair ◽  
Tribological Performance ◽  
Roughness Height ◽  
Roughness Parameters ◽  
Slight Effect ◽  
Wear Process ◽  
Worn Surface

This work investigated the effect of honing morphologies of CuNiCr iron liner on its tribological properties sliding against the Cr-Al2O3 coated piston ring. The worn surface morphology and elements distribution as well as the wear behaviors of CuNiCr iron liner were analyzed to explore the influencing of the honing angle and roughness height on the friction and wear resistance. The results show that the optimized honing angle and roughness can improve the tribological performance of the iron liner, and different tribological characteristics are closely related to different roughness parameters. The wear process of the CuNiCr iron liner against Cr-Al2O3 coated piston rings in sequence was platform flattening, plastic flow, growth of the flakes on the platform edge and flakes debonding. For the smooth surface, the plastic deformed flakes were much fewer due to the low height of the platforms, thus the grooves were not fully filled and there was a slight effect of the debonded debris on the friction pair.

scholarly journals High Temperature Anti-Friction Behaviors of a-Si:H Films and Counterface Material Selection

Coatings ◽  
2019 ◽  
Vol 9 (7) ◽  
pp. 450
Author(s):  
Qunfeng Zeng ◽  
Liguo Qin
Keyword(s):  
High Temperature ◽  
Tribological Properties ◽  
Material Selection ◽  
Friction Pair ◽  
Ceramic Materials ◽  
Low Friction ◽  
Friction Mechanism ◽  
Temperature Oxidation ◽  
Friction Process ◽  
Hydrogenated Amorphous

In the present paper, the influence of self-mated friction materials on the tribological properties of hydrogenated amorphous silicon films (a-Si:H films) is studied systemically at high temperature. The results are obtained by comparing the tribological properties of a-Si:H films under different friction pair materials and temperatures. The a-Si:H films exhibit super-low friction of 0.07 at a temperature of 600 °C, and ceramic materials are appropriate for anti-friction behaviors of a-Si:H films at high temperature. The results of tribotests and observations of the fundamental friction mechanism show that super-low friction of a-Si:H films and ceramic materials of the friction system are involved in high temperature oxidation; this also applies to the tribochemical reactions of a-Si:H films, steel and iron silicate in open air at elevated temperature in the friction process.

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